The ever-popular Duchess Mule sheepskin slipper, crafted from luxurious sheepskin and featuring a durable, slip-resistant sole, offers maximum comfort and warmth, and is available in a wide range of colorways. The Duchess also now boasts DREAM Step® gel-infused memory foam and JUST Guard® for built-in water and stain resistance. Upper - Leather, Lining & Sock - Leather.